Stober 1 Servo Gear Units

Overview
Overhung Load Calculations
Pulling forces or overhung load of
pulleys, sheaves, sprockets, etc. on the
reducer output shaft must not exceed the
allowable limits shown in the load/life/
speed calculations below.
Note: Overhung load is measured at the
center of the shaft extension. No overhung
load is encountered when a reducer is
flange mounted and/or coupling connected
to another unit. However, the shafts of all
components must be accurately aligned
and secured to prevent pre-loading of the
bearings and premature bearing failure.
Use the following formula to determine actual overhung load for a given drive:.
Where:
OHL
HP
kW
D
n
K
Imperial OHL (lbs) =
Metric OHL (N) =
Overhung load (N or lbs)
Horsepower
Transmitted Kilowatt
Pitch Diameter (inches or meters) of Sprocket, Gear, Sheave, Pulley, etc.
Maximum Shaft RPM
126,000 x HP x K
D x n
19,100 x kW x K
D x n
1.00 Single Chain Drive; 1.25 Timing Belt Drive;
1.25 Spur or Helical Gear Drive; 1.50 V-Belt Drive; 2.50 Flat Belt Drive
F Series Load/Life/Speed Calculations
The permissible load and tilting moment values are based on an output
speed of 20 RPM. For higher speeds the following applies, where n 2
is the
desired speed:
F2AX =
F 2A
3 n 2
20
F 2RX
=
M 2KX
=
The application output tilting moment should be determined by the
following formula:
Where:
F 2a
F 2A
F 2r
F 2R
F 2RB
M 2K
M 2k
F 2R
3 n 2
20
Axial Load at Output Shaft
Permissible Axial Load
Radial Load at Output Shaft
Permissible Radial Load
Acceleration Permissible Radial Load
Rated Tilting Torque
Equivalent Tilting Load
M 2KB Acceleration Tilting Torque
z 2
2 • F 2a
• y 2
+ F 2rb
• (x 2
+ z 2
)
M 2A
= < M 2K
1000
Distance Factor
M 2K
3 n 2
20
All formulas shown are based on METRIC values
Upper case letters are permissible values. Lower case letters are for existing values.
–F 2a +F 2a
y 2
+F 2r
–F 2r
x 2
z 2
F Series: OFFSET – Versatile Outputs
800.711.3588 • www.stober.com Servo Gear Units V.28 145